Surface-finished tube.



UNITED STATES PATENT oEEioE.

MARSHALL BURNS LLOYD, OF MENOMINEE, MICHIGAN, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE ELYRIA IRON & STEEL COMPANY, OF EL-YRIA, OHIO, A CORPORA- TION 0F OHIO.

SURFACE-FINISHED TUBE` Specification of Letters Patent.

Patented Apr. 11, 1916.

Original application filed August 7, 1912, Serial No. 713,851. Divided and this application filed September T o all whom it 'may concern Be it known that I, MARSHALL B. LLOYD, a citizen of the United States, and a resident of Menominee, county of Menominee, and the State of Michigan, have invented a certain new, useful, and Improved Surface- Finished Tube, of which the following is the specification.

My invention relates generally to the tube making industry and l-fhas particular reference to the surface finish'or polish of metal tubing.

The general object of my invention is to provide tubing which shall present a pleasing appearanceVwhich shall contain an exterior surface well adapted to prevent rusting and corrosion of the tube7 and which shall be capable of rapid and economical production.

My invention consists generally in the novel article of manufacture'hereinafter described and claimed and will be more readily understood by reference to the accompanying drawings in which I have depicted the novel tubing and the stages of its production. i

In the drawings Figure 1 is a perspective view of a portion of rolled strip metal such as is much used in the formation of welded tubing. Fig. 2 is a somewhat enlarged view showing the strip converted into a tube; and Fig. 3 is a perspective view of the tube in the surface finished or highly polished condition.

Tubing is used in many industries where a pleasing appearance or finish isl desirable, but which require tubing of comparatively low cost. Hence such processes as nickeling, copper finishing, and the like are prohibitive. There are other reasons why a linished or highly polished tube is desirable for many uses, one of which is that tubing formed by any of the known processes, when it emerges from the forming mechanism is rough and somewhat abraded, and, therefore, particularly susceptible to rust. It is my purpose to provide, as an article of manufacture, tubing combining the' desirable features above enumerated, and which shall cure the defects present in the tube as formed by the usual tube forming processes This application is related to and is a divisional art of my pending application, Se-

Vrial No. 13,851, filed August 7th, 1912, for

Serial No. 790,775.

process of reducing and surface finishing metal tubes, rods and the like. The process there described and the mechanism shown for practising that process are well adapted to produce my improved surface finished or polished tube, and will be found of great assistance in the rapid and economical manufacture of this article.

Referring to the drawings, 1 represents a strip ofgzolled metal such as is much used in the formation of welded, brazed, and drawn tubing. In the process of forming the strip metal` which Aconsists in passing a billet through a series of reducing rolls, the metal is given a grain which runs longitudinally of the strip. For clearness of illustration I have depicted the grain by a plurality of longitudinal lines 2. The strip metal 1 is passed through suitable shaping mechanism wherein it assumes the shape'of a tube and then by passing the tube through welding or other mechanism its seam edges are joined, presenting finally the appearance of a seamless tube, as illustrated in Fig. 2. The shaping of the strip metal into tubular form does not materially alter the grain because the forming mechanism a plies substantially the' same general forcgs to the metal as the mechanism which originally produced the strip. The grain, there\.

fore, runs longitudinally of the tube both within and without, as shown. Tubing which is formed by the so-called seamless drawing process also presents a longitudinal grain. Therefore, Fig. 2 may represent either a drawn tube or a welded tube, and when I refer to it as a seamless tube the term should be construed to include a tube which has been welded; one which has been produced by drawing, or one which has been produced by any other process, as I am not here concerned with the-` initial formation of the tube, but instead this application has to do only with finished' or polished tub-V course ofbusiness, is a considerable .'period. Generally it is sufficient to finish only the exterior of the tube, as that surface is the one Which is most susceptible to rust and because it is the visible surface. I find that byl changing the grain upon the surface of the tube and by making-a curclunferentially,

fine grain thereonfthat I can produce a siurface finish or polish which will be effective for the uses intended and which, at the same time, can be rapidly and economically pro-l duced. I have indicated in Fig. 3 a tube embodying my invention with the outer surface thereof finished or polished, and the inner surface left in its initial 0r unfinished state. The grain 2 upon the innerlsurface of the tube runs longitudinally thereof while the grain 3 upon the-outer surface runs circumferentially of the tube; I have indicated the grain 3 as extending slightly into the tube, that is, it appears asa surface skin, as will be seen by reference to the end lpart to the outer surface of the tube a 4thin skin or layer grain extending circumferentially of the tube. By providing the rolls of hardened steel with/highly finished surfaces and by providing a suitable lubricant, a tube, such as emerges. from the forming mechanism, can be highly finished by a simadmirably to prevent the tube :tromrustA` in g, and produces a finish which approximates that of .a nickled tube.- Any roughness or abrasion caused by the tube forming mechanism is entirely obliterated,j and where the tube has a Welded seam, the seam is made invisible. Strictly speaking my novel tubing is the product of the process and apparatus shown in said prior application Serial No. 713,851. It was never produced until that process was invented and I know of no other way in which it may be produced.

I claim: l

A new article of manufacture comprising a metal tube chiefly characterized by the longitudinal trend or graining of the metal` but resenting a .brilliantly smooth minor portion, constituting an outer skin, in which the metal has a distinguishable circumferential trend. 5

In testimony whereof, I have hereunto i set my hand, this 16th day of Sept., 1913,

in the presence of two subscribing Witnesses.

MARSHALL BURNS LLOYD.

Witnesses: I

ERNEST J. RIsDoN C. M. ESTES. 

